The romantic ups and downs of accountant Mollie Jensen (Kirstie Alley) are viewed cynically by a most unusual bystander -- her talking newborn, Mikey (Bruce Willis). She becomes pregnant through an affair with a married man, Albert (George Segal), and then counts on the friendship of taxi driver James (John Travolta) once she discovers Albert is a lying cad. Although Mikey likes James, and James cares for both the baby and Mollie, she isn't sure she can settle down with a blue-collar boyfriend.